UK supermarket Tesco has announced that it will be trialling a deposit return scheme (DRS) in several of its stores around the country. This is great news – countries with effective DRS schemes collect up to 97% of bottles, so Tesco’s trial is a step in the right direction towards reducing the amount of plastic that ends up in our oceans.

But as the UK government prepares to announce a consultation on introducing deposit return schemes across the UK, Tesco should make sure the example it’s setting is the right one. Whilst it’s positive that Tesco and other supermarkets are publicly showing the government that they support DRS, other companies are lobbying the government to limit the scope of any scheme they introduce. Therefore for Tesco’s support to be helpful in the fight to cut plastic pollution, they must make clear that they are fully behind a comprehensive and effective DRS.

But what does this look like? At the moment Tesco have said that their deposit return scheme is limited to bottles that are 750ml or less. But limiting the size of drinks containers that can be returned (or the material they’re made from) would seriously undermine the effectiveness of a nationwide deposit return scheme. If a national scheme was limited to 750ml, you’d be excluding almost 3.3 billion bottles – so if businesses and the government are serious about tackling plastic waste it doesn’t make sense to exclude these larger containers. If schemes are being put in place and machines and infrastructure is being installed, then why limit what can be processed?

Deposit return schemes work by adding a small ‘deposit’ to drinks containers, which you then get back when you return your empty bottle or can. The more bottles that are returned, the more can be recycled – leading to less plastic ending up in landfill, as litter or in the ocean. Countries such as Sweden and Germany have been running successful deposit schemes for years – and worldwide about 150 million people use DRS. Earlier this year the UK government announced that they will introduce nationwide deposit return schemes – but what these will look like is yet to be decided.

For deposit return schemes to be effective in reducing plastic pollution then they need to be done properly – designed to be easy to use and include all sizes and types of drinks containers. Tesco aren’t the first supermarket to trial in-store deposit return schemes – Iceland and Morrisons have also been running trials in selected stores. It’s great to see these supermarkets showing the government their support for deposit return schemes (and showing them how it can be done), but Tesco and others should make sure they take this opportunity to publicly support a fully comprehensive scheme and make it clear the size limit in their trial is not what they’re lobbying for behind closed doors.